Proteomic and transcriptomic characterisation of FIA10, a novel murine leukemic cell line that metastasizes into the brain

by Ursula Just, Helmut Burtscher, Sylvia Jeratsch, Meike Fischer, Carol Stocking, Jens Preussner, Mario Looso, Ralf Schwanbeck, Stefan Günther, Ralf Huss, Lynne Mullen, Thomas Braun

Brain metastasis leads to increased mortality and is a major site of relapse for several cancers, yet the molecular mechanisms of brain metastasis are not well understood. In this study, we established and characterized a new leukemic cell line, FIA10, that metastasizes into the central nervous system (CNS) following injection into the tail vein of syngeneic mice. Mice injected with FIA10 cells developed neurological symptoms such as loss of balance, tremor, ataxic gait and seizures, leading to death within 3 months. Histopathology coupled with PCR analysis clearly showed infiltration of leukemic FIA10 cells into the brain parenchyma of diseased mice, with little involvement of bone marrow, peripheral blood and other organs. To define pathways that contribute to CNS metastasis, global transcriptome and proteome analysis was performed on FIA10 cells and compared with that of the parental stem cell line FDCP-Mix and the related FIA18 cells, which give rise to myeloid leukemia without CNS involvement. 188 expressed genes (RNA level) and 189 proteins were upregulated (log2 ratio FIA10/FIA18 ≥ 1) and 120 mRNAs and 177 proteins were downregulated (log2 ratio FIA10/FIA18 ≤ 1) in FIA10 cells compared with FIA18 cells. Major upregulated pathways in FIA10 cells revealed by biofunctional analyses involved immune response components, adhesion molecules and enzymes implicated in extracellular matrix remodeling, opening and crossing the blood-brain barrier (BBB), molecules supporting migration within the brain parenchyma, alterations in metabolism necessary for growth within the brain microenvironment, and regulators for these functions. Downregulated RNA and protein included several tumor suppressors and DNA repair enzymes. In line with the function of FIA10 cells to specifically infiltrate the brain, FIA10 cells have acquired a phenotype that permits crossing the BBB and adapting to the brain microenvironment thereby escaping immune surveillance. These data and our model system FIA10 will be valuable resources to study the occurrence of brain metastases and may help in the development of potential therapies against brain invasion.

IMPAACT: IMproving the PArticipAtion of older people in policy decision-making on common health CondiTions - a study protocol

Introduction

Rapid population ageing is a demographic trend being experienced and documented worldwide. While increased health screening and assessment may help mitigate the burden of illness in older people, issues such as misdiagnosis may affect access to interventions. This study aims to elicit the values and preferences of evidence-informed older people living in the community on early screening for common health conditions (cardiovascular disease, diabetes, dementia and frailty). The study will proceed in three Phases: (1) generating recommendations of older people through a series of Citizens’ Juries; (2) obtaining feedback from a diverse range of stakeholder groups on the jury findings; and (3) co-designing a set of Knowledge Translation resources to facilitate implementation into research, policy and practice. Conditions were chosen to reflect common health conditions characterised by increasing prevalence with age, but which have been underexamined through a Citizens’ Jury methodology.

Methods and analysis

This study will be conducted in three Phases—(1) Citizens’ Juries, (2) Policy Roundtables and (3) Production of Knowledge Translation resources. First, older people aged 50+ (n=80), including those from traditionally hard-to-reach and diverse groups, will be purposively recruited to four Citizen Juries. Second, representatives from a range of key stakeholder groups, including consumers and carers, health and aged care policymakers, general practitioners, practice nurses, geriatricians, allied health practitioners, pharmaceutical companies, private health insurers and community and aged care providers (n=40) will be purposively recruited for two Policy Roundtables. Finally, two researchers and six purposively recruited consumers will co-design Knowledge Translation resources. Thematic analysis will be performed on documentation and transcripts.

Ethics and dissemination

Ethical approval has been obtained through the Torrens University Human Research Ethics Committee. Participants will give written informed consent. Findings will be disseminated through development of a policy brief and lay summary, peer-reviewed publications, conference presentations and seminars.